Concrete pavement types: JPCP, JRCP, and CRCP explained for the field

Rigid pavement and the three families in one picture

Rigid pavement is a slab of portland cement concrete stiff enough to carry traffic by bending across a wide footprint, spreading the wheel load thin before it ever reaches the dirt. That stiffness is the whole identity of the type. An asphalt pavement is flexible and leans on the layers and the soil under it. A concrete slab is the structure, and it picks the load up and bridges it like a beam. The pressure that lands on the subgrade is low and spread out, which is why a rigid pavement can ride over a soft spot that would rut a flexible one.

Concrete pavement is not one thing. It comes in three families, set apart by one decision: how the slab handles the cracking that concrete is going to do no matter what. Jointed plain pavement controls the crack with joints and carries no steel in the slab. Jointed reinforced pavement spaces the joints wider and adds steel to hold the cracks that form between them. Continuously reinforced pavement throws out the transverse joints entirely and lets a heavy steel mat hold the slab together as it cracks. Same material, three answers to the same problem.

This guide is about choosing and building among those three, plus the specialty slabs that share the rigid family: whitetopping over asphalt, pervious concrete, and roller-compacted concrete. The placing, jointing, sawing, and curing that every one of them needs lives in the concrete pavement jointing and curing guide, and the choice between concrete and asphalt in the first place lives in the asphalt vs concrete comparison. Read this for the type. Read those for the build and the material call.

What is the difference between rigid and flexible pavement?

Rigid pavement is concrete and flexible pavement is asphalt, and the difference is how each one moves the wheel load down to the subgrade. A concrete slab is rigid, so it acts as a beam. It bends a little under the axle, picks the load up, and carries it across a wide area in bending. The stress that reaches the soil is low because the slab did the spreading. The flexural strength of the concrete is the structure.

Flexible asphalt does not bridge anything. It takes the load at the surface and passes it down through the asphalt, the base, and the subbase in a widening cone, so the pressure right under the tire is high and the soil under it carries real stress. The strength lives in the stack and the subgrade, which is why a weak soil forces a thicker flexible section while a rigid slab is less fussy about what is under it, as long as the support is uniform.

The two die differently because they carry differently. Flexible pavement fails by fatigue cracking from the bottom of the asphalt and by rutting in the wheel paths. Rigid pavement fails at its joints and edges, faulting and corner breaks when the support washes out from under a slab. The full material tradeoff, first cost against life and where each one wins, is the asphalt vs concrete comparison. Here it is enough to know the rigid slab spreads the load, and the type families are all variations on how that slab is held together.

Why does concrete pavement crack?

Concrete shrinks as it cures and dries, and it keeps expanding and contracting with temperature for the rest of its life. The slab's own weight and the friction of the subbase restrain that movement, and restrained shrinkage builds tensile stress. Concrete is strong in compression and weak in tension, so when the stress beats the tensile strength, the slab cracks. There is no mix and no admixture that prevents it. The crack is coming. The only question is whether you control it.

The three pavement types are three strategies for that one fact. JPCP says crack where I tell you: it saws closely spaced joints, planes of weakness that pull the crack down to a chosen line, and puts no steel in between. JRCP says I will let the panels run longer and use steel to hold the mid-panel cracks tight when they show up. CRCP says crack as often as you like: it packs in enough continuous steel that the slab cracks every few feet in fine hairlines the steel clamps shut, and it skips the transverse joints altogether.

So the families are not really about reinforcement for strength. They are about crack management. The mechanics of jointing, sawcut timing, and depth, the part that decides whether the crack actually lands under your joint or wanders off on its own, is worked out in the concrete pavement jointing and curing guide. What matters here is that each type is a different deal with the same crack.

The three families: JPCP, JRCP, and CRCP

The three families sort by two things: how much steel rides in the slab, and how the transverse cracking is handled. Get those two straight and the rest follows.

Jointed plain concrete pavement, JPCP, is the common one. No structural steel in the slab, only dowels and tie bars at the joints, and crack control by closely spaced contraction joints, commonly on the order of 15 ft. Jointed reinforced concrete pavement, JRCP, widens the joints to 30 ft or more and adds a light mat of distributed steel, on the order of 0.15 to 0.25 percent of the cross-section, to hold the intermediate cracks tight. Continuously reinforced concrete pavement, CRCP, carries a heavy continuous longitudinal mat, commonly 0.6 to 0.8 percent of the cross-section, and no transverse contraction joints at all. The numbers move with the agency and the design, so treat them as the shape of each type, not as spec values.

The table is the quick read. Build the type the plans call for, the way the plans detail the steel and the joints, because the choice is a structural design decision, not a field substitution.

JPCP: jointed plain concrete pavement

Jointed plain concrete pavement is the workhorse of the trade, the type under most concrete streets, parking lots, aprons, and a large share of highway mainline. The defining feature is what it does not have: no reinforcing steel in the body of the slab. It controls cracking entirely with geometry, by sawing contraction joints close enough together that the slab relieves its shrinkage stress at the joints before it can build enough tension to crack a panel in the middle.

The only steel in JPCP sits at the joints. Smooth dowel bars cross the transverse joints to transfer the wheel load from slab to slab. Deformed tie bars cross the longitudinal joints to hold adjacent lanes together. Neither one reinforces the slab against bending. Their jobs are load transfer and keeping the lanes tied, which is a different thing entirely from the distributed steel in the other two types.

Panel size is everything in JPCP. The joint spacing is tied to the slab thickness, and the panels are kept close to square, because a slab much longer than it is wide cracks across the middle no matter how the joints are placed. Get the spacing and the aspect ratio right and a JPCP pavement runs decades on little more than joint sealing. Get them wrong, space the joints too far apart or let panels go long and skinny, and the slab makes its own mid-panel crack, which is exactly the failure JRCP was invented to live with. The spacing rules and the sawcut window are in the jointing and curing guide.

JRCP: jointed reinforced concrete pavement

Jointed reinforced concrete pavement takes a different bet. Instead of keeping the panels short to prevent mid-panel cracks, it lets the joints run far apart, 30 ft or more, accepts that the long panels will crack somewhere in the middle, and puts a light mat of steel in the slab to hold those cracks tight when they form. The steel is not there to carry the bending load. It is there to keep the inevitable transverse crack from opening into a working joint that faults and lets water in.

The steel content is modest, commonly in the range of 0.15 to 0.25 percent of the cross-section, distributed mesh or bars set in the slab. Wider joints mean fewer joints to build and seal, which was the appeal, but the wider spacing also means each joint opens more with temperature, so JRCP joints need dowels and good sealing to survive the larger movement.

JRCP was common in older highway construction across a lot of the country and you still drive on plenty of it. In new work it has largely fallen out of favor, squeezed between JPCP, which is simpler and cheaper to build with no slab steel, and CRCP, which goes the whole way to continuous reinforcement for the heaviest traffic. If you are repairing JRCP, the thing to understand is that the mid-panel cracks are by design and the steel is holding them. The failures to chase are the ones where that steel has corroded or the joints have lost load transfer.

CRCP: continuously reinforced concrete pavement

Continuously reinforced concrete pavement is the premium type, built for the heaviest traffic and the longest life. It carries a heavy continuous mat of longitudinal steel, commonly 0.6 to 0.8 percent of the cross-section, running the length of the pavement, and it has no transverse contraction joints at all. That last part throws people. A pavement with no contraction joints sounds like a pavement that will crack uncontrolled, and that is exactly what it does, on purpose.

CRCP is designed to crack. The continuous steel forces the slab to relieve its shrinkage in a pattern of fine transverse cracks spaced every few feet, commonly 3 to 6 ft apart, instead of a few wide cracks far apart. The steel holds each of those cracks tight, on the order of a few hundredths of an inch wide, tight enough that the crack faces stay locked together and keep transferring load across the crack by aggregate interlock. A tight, held crack is not a defect in CRCP. It is the mechanism.

The payoff is a pavement with no transverse joints to saw, seal, or maintain, which on a high-volume corridor is most of the lifetime maintenance gone. A well built CRCP can run for decades approaching zero joint maintenance, which is why agencies put it on heavy urban interstates and some airport pavements where the traffic runs to tens of millions of load repetitions and a lane closure is its own expensive event.

The catch is the steel. CRCP lives or dies on the amount, the depth, and the laps of that continuous reinforcement, and on the terminal treatments at the ends where the slab wants to move. There is more steel and more first cost, and the construction is less forgiving than JPCP. Skimp the steel and the cracks come wider and farther apart, which leads to punchouts, where the slab between two cracks works loose. Build CRCP to the structural drawings, because the steel placement is the pavement.

What is the difference between JPCP and CRCP?

The difference is the steel and the joints, and they trade off against each other. JPCP has no steel in the slab and many transverse joints. CRCP has heavy continuous steel and no transverse joints. Everything else about how the two perform follows from that single swap.

JPCP manages cracking by preventing mid-panel cracks: short panels, closely spaced joints, dowels to carry load across each joint. The maintenance is the joints, sealing them and keeping load transfer alive, and a JPCP pavement is cheaper and simpler to build because there is no slab steel to place. CRCP manages cracking by embracing it. It cracks every few feet and the continuous steel holds those cracks tight, so there are no transverse joints to maintain at all. The maintenance is almost nothing for a long time, but the first cost is higher and the steel placement has to be right.

So the choice is first cost and simplicity against long-life, low-maintenance performance under heavy traffic. JPCP is the default for streets, lots, and ordinary highway work. CRCP earns its higher cost on the heaviest, busiest corridors where the traffic is relentless and you cannot afford to close lanes for joint work. The structural designer and the agency pavement-type policy settle which one a given project gets. It is not a field call.

What are dowel bars, and what do tie bars do?

A dowel bar is a smooth, round steel bar set across a transverse joint to carry the wheel load from one slab to the next. As a tire crosses the joint, the loaded slab wants to deflect down while the next slab does not. The dowel ties their vertical movement together so the load transfers across instead of slamming the edge of the next panel. At least one end of the dowel is greased or sleeved so it slides, which lets the joint open and close with temperature while the bar still carries the vertical load. A dowel that is bonded on both ends has become a tie bar by accident, and it will lock the joint and crack the slab.

Tie bars do the opposite job. They are deformed, bonded full length, set across longitudinal joints, and they do not transfer load and do not slide. Their job is to hold adjacent lanes or panels tight together so the longitudinal joint does not creep open and lose its own load transfer through aggregate interlock. Smooth dowels carry load and let the slab move. Deformed tie bars hold the slab together and stop it from moving. Same family, opposite intent, and swapping them is one of the classic costly errors.

Why dowels matter at all is faulting. With no load transfer across a transverse joint, each slab deflects on its own under the wheel, the leading slab pumps water and fines out from under its edge, and one slab settles below the next. That step is faulting, and it beats the ride and the slab edges to death. Dowels keep the two slabs deflecting together so the load shares across the joint and the pumping never gets started. The sizing, the placement in baskets or by inserter, and the alignment tolerances are detailed in the jointing and curing guide. The point here is that the dowel is the load-transfer device and the tie bar is the lane tie, and the two are not interchangeable.

How thick should a concrete pavement be?

Slab thickness carries the load in a rigid pavement, and it comes out of a structural design, not a rule of thumb. The slab is the structure, so its thickness is the main lever the designer has, set against three inputs: the traffic the pavement will carry over its life, the support under the slab, and the strength of the concrete itself. Push any of those up or down and the required thickness moves.

The support under the slab is captured by the modulus of subgrade reaction, the k-value, which is how stiff the foundation is in terms of pressure per unit of deflection. It runs from around 50 pci on weak support to over 1000 pci on strong support, and it is measured by a plate bearing test or estimated by correlation with other soil tests. When the slab sits on a subbase rather than straight on the soil, the design uses a composite k that credits the added support of the base layer. A higher k means a stiffer foundation and a thinner slab for the same traffic, though the rigid slab is far less sensitive to the foundation than a flexible pavement is.

Traffic is the other big input, counted in equivalent load repetitions over the design life, and the concrete's flexural strength rounds it out, because a rigid pavement fails in bending and the modulus of rupture is what resists it. The design runs through AASHTO methods, the 1993 guide or the mechanistic-empirical Pavement ME, or an agency procedure. The exact thickness, the k-value used, and the traffic inputs are spec items set by the engineer. Carry the relationships in your head, but never carry a thickness number from one job onto another.

The subbase and uniform support

A rigid pavement is only as good as the support under it, and the word that matters is uniform, not strong. The slab is stiff enough that it does not need the structural support a flexible pavement leans on, but it needs the support to be the same from one end of a panel to the other. A slab that sits on stiff ground in one spot and soft ground in the next bends to bridge the gap and cracks from the bending. Consistency beats raw strength here.

The subbase is the engineered layer between the prepared subgrade and the slab, and its real jobs are uniform support, drainage, and not pumping. Water is the enemy. Let water sit under the slab and truck traffic pumps it out through the joints and cracks, carrying fines with it, and now there is a void under the slab edge. The slab loses its support right where the load crosses, the panels rock, and you get faulting and corner breaks. A free-draining, non-erodible subbase, often a stabilized or treated base on heavy-traffic work, keeps that from starting.

This is the failure that traces back to the base on a pavement that looked fine the day it was poured. The mix can be right, the joints sawed on time, the cure clean, and the slab still fails in a few years because the support washed out from under the edges. Build the base uniform, keep water out and moving, and the slab on top gets to do its job. The placing details for getting the slab onto that base are in the jointing and curing guide.

Whitetopping: concrete over asphalt

Whitetopping is a concrete overlay placed over an existing asphalt pavement, a rigid wearing surface built on a flexible base. It is a rehabilitation move more than a new-pavement type, but it is concrete pavement and it cracks and gets jointed like any other. On a milled and cleaned surface the concrete bonds to the asphalt and the two layers act together as a composite, which lets the concrete run thinner than it could standing on its own.

The bonded versions come thin and ultra-thin, on the order of 2 to 6 in, and they fit the spot where asphalt has rutted and shoved under slow heavy loads but the base underneath is still sound: intersections, bus lanes, ramps, and lot areas that rut. You put a rigid surface where the load needs one, reuse the existing asphalt as structure, and get a longer-lived surface than another asphalt overlay would give in the same place. Thin whitetopping uses short joint spacing in small panels, because the thin slab needs the load relief.

Thicker unbonded whitetopping behaves more like a new concrete pavement riding on an asphalt base, designed for heavier work. The material choice of concrete over asphalt, and where whitetopping fits against another asphalt overlay, is worked through in the asphalt vs concrete comparison. The construction is concrete pavement construction, jointed and cured the same way. The thing to get right is the bond, because the composite action that lets the slab run thin only exists if the concrete is actually bonded to a clean, milled asphalt surface.

Pervious concrete pavement

Pervious concrete is a rigid pavement built to let water through it, the opposite of every other slab in this guide. The mix is gap-graded, almost no fine aggregate, so it sets up with an interconnected web of voids, commonly 15 to 25 percent of the volume, that water drains straight through into a stone reservoir and the soil below. It is a stormwater tool first and a pavement second, used to cut runoff, recharge groundwater, and meet stormwater regulations on parking lots, walkways, and low-speed areas.

The trade-off is strength. Take the sand out of the mix and you give up compressive strength, so pervious runs well below conventional concrete, commonly around 1500 to 2500 psi, which is why you see it on light-duty pavements and not on truck routes or highways. It also has its own maintenance. The voids clog with sediment over time and the surface has to be vacuumed or pressure-washed to keep it draining. The failure mode is a pervious pavement that no longer drains because nobody cleaned it.

Pervious is its own discipline with its own placement and curing rules, different from a standard slab, and the mix design and the reservoir under it are engineered to the rainfall and the soil infiltration. Treat it as a stormwater structure that happens to carry light traffic, and build it to that design.

Roller-compacted concrete (RCC)

Roller-compacted concrete is a rigid pavement built like asphalt. It is a stiff, zero-slump concrete, the same cement, water, and aggregate as any other, but dry enough to hold a shape under a roller. It goes down through an asphalt paver and gets compacted with vibratory rollers, with no forms, no finishing, no dowels, and no reinforcing steel. That is the appeal. It builds fast and cheap and carries heavy loads.

Because there is no slab steel and often no sawed joints, RCC controls its cracking the way a jointless slab does, by cracking at random and relying on the tight crack faces to transfer load through aggregate interlock. Left unsawed, the random cracks tend to land 15 to 30 ft apart and stay tight enough to work. Some jobs do saw joints into RCC where appearance or crack control matters, but the industrial version often skips them entirely, which is where the joint-maintenance savings come from.

RCC found its home in heavy industrial pavement: port and intermodal terminals, distribution centers, logging and equipment yards, tank pads, and heavy parking and storage areas. The loads are heavy and slow, exactly where a rigid pavement belongs, and the appearance and ride tolerances are loose enough that you can skip the forming and finishing. It opens fast, often to light traffic within hours and heavy traffic in a day or two. Where it needs a smoother ride, an asphalt or thin concrete surface goes on top. For a heavy yard where speed and cost rule and a perfect ride does not, RCC is hard to beat.

Why is my concrete pavement faulting and pumping?

Faulting and pumping are the signature failures of jointed rigid pavement, and they run together. Faulting is the step that builds at a transverse joint when one slab settles below its neighbor, the bump you feel at every joint on a worn concrete road. Pumping is water under the slab being forced out through the joint under traffic, carrying fines from the subbase with it. One feeds the other. Pumping erodes the support under the slab edge, the unsupported edge deflects more under load, which pumps more water and erodes more support, until the slab faults and the corners break.

The root cause is lost load transfer plus water. A joint with good dowels and a sealed surface keeps the two slabs deflecting together and keeps water out of the subbase, and it does not fault. A joint with missing, undersized, or misaligned dowels lets each slab deflect on its own, and an unsealed joint lets surface water down to the base. Take away the load transfer and let the water in and you have built the faulting in. On undoweled pavement that relied on aggregate interlock alone, the interlock wears out over the years and load transfer drops below the point where the joint can carry the wheel.

Misaligned dowels are their own quiet failure here. A dowel only works if it is straight and aligned along the line of travel, free to slide as the joint opens and closes. Tip it, skew it, or set it too high or low and the bar binds when the slab moves, locking the joint. A locked joint forces the movement out somewhere else, usually as a crack beside the joint or a spall right over the bar, and it kills the load transfer the dowel was placed to provide. The alignment is inspected hard for exactly this reason, and the inspection details are in the jointing and curing guide. The other distress to know is the corner break, from loss of support at the slab corner, and on CRCP the punchout, where the slab between two closely spaced cracks works loose when the steel or the support has failed.

Concrete pavement repair: full-depth, partial-depth, dowel bar retrofit

Rigid pavement repair sorts by how deep the problem goes and whether the slab still has load transfer. Three techniques cover most of it, and picking the right one starts with reading why the slab failed, not just patching where it shows.

Full-depth repair cuts out and replaces the entire slab thickness over the failed area, down to the base, and it is the answer for a slab that has cracked through, a corner break, or a section over a pumped-out void. The repair is dowelled to the slabs it joins so the new patch carries load across its joints, and it has to cure to strength before it opens, which is why concrete repairs take a lane longer than an asphalt patch. Partial-depth repair handles distress that is only in the top of the slab, spalling and surface deterioration around joints, by milling out the bad concrete and replacing just that, leaving the sound lower slab in place.

Dowel bar retrofit is the one worth knowing by name, because it fixes faulting without replacing the slab. On a jointed pavement that is faulting from lost load transfer but is otherwise sound, the crew saws slots across the joint, sets new dowel bars in them, backfills with a fast patching material, finishes, and diamond grinds the surface smooth. It restores the load transfer the original joint lost and can add 10 to 15 years to a pavement that would otherwise need replacing. Diamond grinding on its own restores the profile and texture and is often paired with the retrofit. Match the repair to the failure: surface distress gets partial-depth, structural failure gets full-depth, and lost load transfer on a sound slab gets the dowel bar retrofit.

Which concrete pavement type should you use?

The type is a structural design decision driven by traffic, design life, maintenance tolerance, and first cost, and on agency work it is settled by a formal pavement-type-selection process, not a preference. The relationships are simple enough to carry in your head even though the final call belongs to the engineer.

JPCP is the general-purpose answer and the right default for the large majority of work: streets, parking lots, aprons, and ordinary highway mainline. It is the cheapest and simplest of the three to build, it has a long track record, and it performs well when the joints are spaced and dowelled right. Reach for CRCP when the traffic is heavy and relentless and you want the longest life with almost no joint maintenance, the heavy urban interstate and the busy corridor where a lane closure for joint work is its own expensive problem. JRCP rarely gets specified in new work. You mostly meet it on older highways you are maintaining.

The prior question, concrete or asphalt at all, comes before the type question, and that one turns on the load, the climate, the budget, and the life-cycle cost. It is worked through in the asphalt vs concrete comparison. Once concrete is chosen, the type falls out of the traffic and the agency's policy: ordinary loads and budgets get JPCP, the heaviest corridors get CRCP, and the specialty cases, a stormwater lot or a heavy industrial yard, point to pervious or RCC. Let the design and the pavement-type policy settle it, and build the type the plans detail.

Heavy industrial and data-center slabs

Heavy industrial and critical-facility slabs are where rigid pavement is the obvious answer, because the loads are heavy, concentrated, and often parked in one place for hours. A container yard with loaded reach stackers, a port or intermodal terminal, a distribution dock, a crane hardstand, a data-center generator or transformer pad: these see point loads and sustained weight that would rut and shove asphalt, and sometimes fuel and oil that asphalt cannot live with. The rigid slab spreads the point load over a wide footprint and stays put under sustained weight, which is the property that makes it right here.

What changes on a heavy-load slab is the engineering, not the principles. The slab is thicker, the reinforcement and dowels are sized to the real equipment loads, and the subbase and drainage matter even more, because a void under a heavily loaded slab edge fails fast. Isolation joints go around the equipment, the foundations, the bollards, and the conduit stub-ups so the pad does not pry on what it serves. For the biggest heavy-duty yards, roller-compacted concrete is often the economical pick, since the loads are heavy and slow and the ride tolerances are loose enough to skip the forming and finishing.

Treat these as designed structures and build to the structural drawings. The load is the reason the pavement is concrete in the first place, so the thickness, the steel, and the joint layout are not the place to value-engineer on the fly. Differential settlement next to a building full of equipment that cannot tolerate movement is a real failure, not a cosmetic one, and the geotech and the engineer set the slab and the subgrade work to the loads on the drawings.

What to document

Come back to a panel that cracked or a joint that faulted a year out, and you need to know what was actually built before you can say why it failed. The record is what tells you which type was built, what steel went in, how the joints were laid out, and whether the slab was opened at strength. Capture it by pavement section as you build, because a big site often has more than one type: concrete pads and asphalt drives, a JPCP lot and a CRCP entrance road.

For each section, record the pavement type, the slab thickness and mix, the reinforcement (none for JPCP, the mat and percentage for JRCP or CRCP), the dowel and tie bar size and spacing, the joint type and spacing, the subbase type and support, and the strength the slab was opened on. Note the design source, the spec section and the structural drawing, so the next person can trace why the pavement is what it is. The detailed placing, sawing, and curing record lives in the jointing and curing guide's documentation. What this table adds is the type-level decisions the construction record sits under.

Common mistakes

• Spacing the contraction joints too far apart for the slab thickness, so a JPCP panel cracks in the middle where there is no steel to hold it.
• Confusing dowels and tie bars: smooth sliding dowels where lanes need tying, or bonded tie bars across a joint that has to open and close.
• Leaving dowels out or setting them misaligned, so the joint loses load transfer and faults, or binds and locks and cracks the slab.
• Building the slab on a soft or non-uniform subbase that pumps, so the support washes out from under the edges and the panels fault.
• Sawing the joints late, so the slab cracks at random before the joint is cut. The timing rules are in the jointing and curing guide.
• Specifying the wrong type for the traffic: JPCP joints under relentless heavy traffic that wanted CRCP, or paying for CRCP steel where JPCP would have served.
• Treating CRCP's tight transverse cracks as a defect and chasing them, when the steel is doing its job holding them shut.
• Skimping on the continuous steel amount, depth, or laps in CRCP, where the steel is the pavement and a shortfall shows up as wide cracks and punchouts.

Field checklist

Standards and references

The framework for rigid pavement is spread across a few bodies, and citing the right one is the credibility test. The American Concrete Pavement Association, the ACPA, publishes the working guidance on pavement types, jointing, dowels, and tie bars that the trade leans on. ACI covers the concrete construction side, with ACI 330 for parking lots and the ACI 325 documents for concrete pavement design and construction. The FHWA technical advisories, including the one on CRCP, and the state DOT specs govern roadway and highway pavement, while the Portland Cement Association and the CRSI cover the cement and the reinforcing-steel sides.

Thickness and type design run through AASHTO, the 1993 Guide for Design of Pavement Structures and the mechanistic-empirical Pavement ME, or an agency procedure, with the modulus of subgrade reaction measured by plate bearing test under AASHTO T 221 and T 222 or ASTM D 1195 and D 1196. Materials and test methods carry ASTM and AASHTO numbers, with concrete strength run through compressive and flexural beam tests. The roller-compacted concrete guidance comes from the ACPA and the cement-industry RCC references. Confirm the current edition of each, because they revise on a cycle.

Above all of it sits the project specification and the structural design from the engineer. The pavement type, the slab thickness, the steel, the dowel and tie bar schedule, the joint layout, and the opening strength are spec items, and where a contract calls a number, that number controls over any rule of thumb in this guide. Do not invent a section number on a submittal. Name the requirement, cite the standard you have confirmed, and let the spec settle the value.

Units, terms, and conversions

Concrete pavement carries a vocabulary that shifts between the slab, the spec sheet, and the design report, so the same idea reads a few different ways across a job.

Rigid pavement and PCC, portland cement concrete, pavement mean the same thing, the stiff slab as opposed to flexible asphalt. The three types go by their initials: JPCP for jointed plain, JRCP for jointed reinforced, CRCP for continuously reinforced. Steel content is given as a percentage of the slab cross-sectional area. Slab thickness is in inches on US plans and millimeters on metric ones. The modulus of subgrade reaction, the k-value, reads in pounds per cubic inch (pci) or MPa per meter. Strength reads in psi or MPa, with a flexural modulus of rupture for pavement design and a compressive strength from cylinders. RCC is roller-compacted concrete, and whitetopping is a concrete overlay on asphalt.

Rigid / PCC pavement

A portland cement concrete slab that carries load by beam action, as opposed to flexible asphalt

JPCP

Jointed plain concrete pavement; no slab steel, crack control by closely spaced joints

JRCP

Jointed reinforced concrete pavement; wider joints with light distributed steel holding mid-panel cracks

CRCP

Continuously reinforced concrete pavement; heavy continuous steel, no transverse contraction joints

k-value

Modulus of subgrade reaction, the stiffness of the support under the slab, in pci or MPa/m

Faulting

A vertical step at a transverse joint from lost load transfer and pumping

Punchout

A CRCP distress where the slab between two closely spaced cracks breaks loose

RCC

Roller-compacted concrete, a zero-slump concrete placed by paver and compacted with rollers

Related tools

Calculators and readiness checks for this work

Compare your options

FAQ

People also ask

• How far apart should concrete pavement joints be?
• Is asphalt or concrete better for pavement?
• What is a concrete admixture?
• Why does concrete crack?
• What is concrete formwork?